Threaded sheet metal bung opening



J. FREASE THREADED SHEET METAL BUNG OPENING Filed June 9; 1939 7IIIIIllIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 'IIIIIIIIIIIIlllIIlIIIIIIIIIIIIIi/III/ m r r 7 M :fl

Patented Augl4, 1942 THREADED s mn'r METALBUNG OPENING Joseph Frease, Canton, Ohio, asslgnor, by mesne assignments, to American Flange & Manufacturing 00., Inc., New York, N. Y.,' a corporation of Illinois Application June 9, 1939, Serial No. 278,209

11 Claims.

The invention relates to bung opening constructions for metallic containers, barrels, drums, vessels, packages and the like for shipping, storing and/or dispensing fluid, liquid, or semi-solid materials; and relates more particularly to a reinforced threaded sheet metal neck integral with a sheet metal wall in which the threads are preferably standard pipe threads and in which the threads and reinforcing means may be made of very thin sheet metal if desired.

Moreover, the invention is an improvement upon the threaded sheet metal structures shown in the C. T. Draper Patent No. 2,156,237, dated April 25, 1939, and upon the method and structures disclosed in the copending C. T. Draper patent applications, Serial Nos. 207,285, 246,118, 246,119, which matured into Patent 2,271,762, February 3, 1942, and 269,545.

It is sometimes desired to extend the flange means at the end of a threaded sheet metal bun opening neck structure, of the type shown in said Patent No. 2,156,237, a considerable distance laterally outward of the outer end of the neck. Likewise, it is sometimes desired to provide such flange means with a comer or shoulder against which a liquid sealing gasket is seated by a closure plug screwed into the neck.

Moreover, it is frequently desired to provide a standard pipe threaded sheet metal bung opening neck in quite thin gauge sheet metal. It is likewise frequently desired, if the neck is formed in sheet metal of the thinner gauges, to strengthen the same against distortion due to unusual or extraordinary blows or forces to which the neck may be subjected in use; and to strengthen the resistance of the neck against abnormally or unnecessarily heavy forces which may be transmitted to the same by an attempt to tighten and seat a threaded plug in the neck with a much greater force than necessary.

These characteristics are severally obtainable by the structures shown in said Draper Patent No. 2,156,237, but they are not conjolntly obtainable in such a structure 'if made from metal of quite thin gauges.

It is therefore'an object of the present invention to provide a threaded sheet metal bung opening neck structure with flange means extending a considerable distance laterally outward of the outer end of the neck.

It is also an object of the present invention to provide a comer or shoulder on an outwardly extending flange means on the outer end of a threaded sheet metal bung opening neck structure against which corner or shoulder a closure p11 screwed into the neck may seat a liquid sealing gasket,

Additionally, it is an object of the present invention to provide reinforcing means for a threaded sheet metal bung opening neck structure, which strengthens the neck against distortion due to unusual or extraordinary blows or forces and strengthens the neck resistance to abnormally or unnecessarily large plug seating forces.

Moreover, it is an object of the present invention to provide a threaded sheet metal bung opening neck structure in which each or all of the above characteristics or arrangements may be present and which neck structure may be formed of sheet metal of the thinner gauges if desired.

And finally, it is an object of the present invention to provide a threaded sheet metal bung ,opening neck construction for a metallic conshown in the accompanying drawing and are hereinafter claimed and described in detail.

The present structural improvements may be stated in general terms as including in metallic container bung opening construction, a wall provided with 'a tubular sheet metal neck, preferably integral of the wall, forming a bung opening for the container projecting or extending preferably outwardly of the container from the wall, the neck terminating in outturned annular flange means, the neck being surrounded by a ring forming a part or all of said flange means, the neck and flange means forming an annular shoulder, the neck and ring between the wall and flange means being provided with interfitting complementary internal and external V-sided threads, the internal ring thread being a standard pipe thread; the internal surface of the threaded part of the neck wall, the external surface of the threaded part of the ring wall, and the metal of the threaded part of the neck and ring walls throughout its entire thickness being roller swaged, deformed, cold rolled, ironed, bur nished, spun, flowed, smoothed and hardened into zig-zag thread-like formations with compressed internal neck and external ring thread 5 apices, the threads being preferably displaced gasket interposed between the neck flange means and closure member flange and seated against said shoulder for sealing the opening in a liquidtight manner, and a tamper-proof cap enclosing between wall 9 and neck Ill. The ring l2 also has a threaded portion l and terminates at its upper end-in an outturned flange IE to form with flange ll outturned flange means at the outer the outer end of the threaded closure member and engaging around and under the neck flange means.

The present method improvements may be stated as preferably including the steps of forming a neck in a sheet metal wall, forming a sheet metal ring, telescoping the ring over the neck and preferably spot welding or tack welding the ring to the neck, swaging, deforming, cold rolling, ironing, burnishing, spinning, flowing, smoothing. hardening and working the metal in a portion of said ring and neck simultaneously under pressure between threaded roller dies to form zig-zag thread-like formations preferably displaced inwardly from the tubular loci of the unthreaded parts of the neck and ring to provide internal V -shaped standard pipe threads in the neck, and forming an outturned flange on the outer end of the ring, or on the outer end of the ring and neck either before or after the thread forming operation.

In the drawing:

Figure 1 is a vertical section showing an integral neck drawn in a sheet metal wall, to which a sheet metal ring has been spot welded after being telescoped thereover;

Fig. 2 is a view similar to Fig. 1 showing the neck and ring after V-shaped pipe threads, the internal one of which is a standard pipe thread,

'have been roller swaged therein under pressure between roller dies;

Fig. 3 is a view similar to Figs. 1 and 2 illustrating the neck and ring after flange means has been provided at the outer end thereof;

Fig. 4 is an enlarged view of a portion of Fig. 3;

Fig. 5 is a plan view of the bung ring construction shown in Figs. 3 and 4, closed by a threaded sheet metal plug and sealed by a tamper-proof sealing cap with certain parts broken away;

Fig. 6 is a section taken on the line 6-6, Fig. 5; and

Fig. '7 is a view similar to Figs. 4 and 6 of a.

slightly modified form of construction.

Similar numerals refer to similar parts throughout the various figures of the drawings. Referring particularly to Figs. 4 and 7, the improved bung opening construction is generally indicated at 8 and is formed in a sheet metal wall indicated at S, which may be any wall of a sheet metal container, or may be a sheet metal member secured to a sheet metal container in any suitable manner. The wall 9 is provided with an integral bung opening neck wall "I threaded at Ill-l, preferably having a flange II at its outer end. The only diiference between the construction shown in' Fig. 'I and that of Fig. 4 is that the outer end of the neck In in Fig. 7 is not turned laterally outwardly to form a flange, but

projects upwardly as indicated at Ila.

The threaded neck wall [0 is surrounded by a ring I! preferably having a lower rounded flange I 3 seated against the flllet l4 connecting end of thethreaded neck as in Fig. 4, or to form in itself outturned flange means at the outer end of the threaded neck as in Fig. 7.

In the constructions shown in both Figs. 4 and '7, a shoulder I! or Ha is formed between the end of the neck wall and the ring flange It for a purpose to be later described.

The threaded neck l0 reinforced by ring l2, may be made as best shown in Figs. 1, 2 and 3 by drawing a tubular neck Illa in a sheet metal wall 9and telescoping thereover a sheet metal ring 12a formed with a lower rounded flange l3 seated against the fillet 14 extending between wall 9 and neck lOa. Ring l2a is preferably spot welded at one or more places as indicated at l8 in Fig. l for temporarily holding the ring [2a and neck Illa assembled against relative motion.

The neck [0a with the ring He thus assembled and temporarily held against relative motion, may then be placed in a machine such as shown in the Draper Patent No. 2,145,587 and worked as described. therein or by the method set forth in the Draper Patent 2,271,762 to simultaneously form the interfltting complementary internal external V-sided threads l5 and Ill-l (Fig. 2) in ring |2a and neck Wu.

The threaded portions l5 and I0l of the ring l2 and neck It! are each similar to the threads shown in Draper, Patent No. 2,156,237 and have an accurate V-shape and zig-zag formation resulting from the roller swaging, deforming, cold rolling, ironing, burnishing, spinning, flowing, smoothing and hardening of the metal by being worked under pressure between the roller forming dies.

However, in the present improvements, the roller forming and working of the metal in the neck and reinforcing ring to form the threads therein is accomplished simultaneously in both members and the only purpose of spot welding the members together at I8 is to initially hold them against relative slippage as the roller working operation progresses.

The roller working of the metal to form the threads is quite severe and may be sufficient in some cases to loosen the spot weld [8. However, because the threads are displaced inward of the tubular loci of the unthreaded parts of the neck and ring walls, the interengaged threaded portions l5 and la prevent the ring l2 from relative threaded movement on neck l0.

Thus, if the spot weld fails and it is attempted (Figs. 4 and 7) to screw ring l2 downward on threaded neck [0, rounded flange l3 abuttin against fillet l4 prevents such movement. If it is attempted to screw ring I2 upward on threaded neck 10, the threads l5 of ring l2 cannot pass over neck flange ll (Fig. 4) or neck end Ila (Fig. 7). Thus, the interfltting threaded and unthreaded portions of neck l0 and reinforcing ring l2 hold the same substantially rigid in assembled relation because of the inward displacefnent of the threads formed simultaneously therein by the roller swaging operation.

Either before or after the neck It) and ring l2 have been simultaneously threaded, flanges II and [6 may be turned over to the laterally outwardly extending position best shown in Figs. 3 and 4. If it is desired to provide the construction shown in Fig. 7, ring flange l6 may be turned laterally outwardly either before or after the simultaneous ring and neck threading operation, or flange 16 may be provided in ring l2a prior to telescoping the ring over neck llla.'

As shown in the drawing, the internal threaded surface Ill-l of the threaded neck is a standard pipe thread for receiving a threaded closure member. In Figs. 6 and 7, a threaded sheet metal closure plug generally indicated at I9, is seated in the threaded neck, but any type of standard threaded member may be seated within the threaded neck to form a closure therefor.

Difierent types of such standard threaded closure members are shown for instance in the Draper Patent No. 2,156,237 .and in the Draper applications, Serial Nos. 207,285, 246,118 and If a threaded sheet metal plug 19 is desired, the same may be made in accordance with the method set forth in said Draper application, Serial No. 207,285.

Shoulders H or Ila form an offset abutment against which a single gasket 20 may be seated barrel sheet. This provision amounts to absorbing. the axial stresses in the complementary threaded portions of the neck and reinforcing ring.

If the reinforcing ring extended straight downward from flange II to fillet l4 without any intervening threaded portion l5, interfltting with neck threads, force 23 would be transmitted directly to wall 9, placing the neck metal under tension at M if the plug is tightened too much. This tensional force, in the prior constructions, is in additionto the tortional force to which the neck wall is subjected if the plug is unnecessarily tightened too much. Accordingly, the

in liquid-tight sealing relation by a threaded closure member screwed into the threaded neck; and any suitable tamper-proof cap 2| may be engaged over, around and under the closure member and the flange means on the end of the neck, as shown in Figs. 6 and 7.

The reinforcing ring I2 formed and assembled in accordance with the present improvements discharges a number of functions. First, it provides a means for supplying outwardly extending flange means at the outer end of the threaded neck of a' considerable radial width if desired. Second, the flange IS on the ring l2 forms with the neck a shoulder H or Ila against which the liquid sealing gasket may be seated. Third, the ring [2 strengthensthe neck against distortion due to unusual blows to which the. threaded opening may he accidentally subjected.

A fourth and very important function of the improved construction is that the reinforcing ring transmits the seating reaction of the plug back to the outer threaded part of the neck Ill; and not to the fillet [4, where the neck is joined with the wall 9, as is true in some of the closure constructions disclosed in the Draper patents and applications referred to above.

Inother words, as the closure plug is seated within the threaded neck, the threads of the plug react against the threads of the neck by upwardly and outwardly directed forces as indicated diagrammatically by the arrows 22 in Fig. 4. At the same time, the plug head reacts downwardly on the flange means by downwardly directed forces indicated diagrammatically by the arrow 23 in Fig. 4. These downward forces 23 are in turn transmitted by reinforcing ring' l2 to the outer threadedarea of the neck wall by resultant forces directed inwardly and downwardly, indicated diagrammatically by arrows 24 in Fig. 4. Thus, the resultant tendency,of the forces 22 and 24 is to place the threaded neck wall under compression, which it can readily withstand, even though the plug is unnecessarily tightened too much.

As will be evident, the stresses incident to the tightening of the plug will force the engaging sides of the thread formations Ill- 1 and 15 together with stresses whose intensities decrease in the successive interengaging thread conformations starting from the outer flanged end to present improvement enables the threaded neck II and wall 9 to be formed of extremely thin gauge metal because a tensional pull at fillet l4 due to tightening of a plug in the neck too tight, is eliminated.

Accordingly, the present invention provides an improved standard threaded bung opening construction for metallic containers made of sheet metal of the thinner gauges, although it is clear that the improved construction can also be advantageously used in containers made from sheet metal of the heavier gauges.

In the foregoing description, certain terms have been used for brevity, cleamess and under standing; but no unnecessary limitations areto be implied therefrom beyond the requirements of the prior art; because such words in being used for descriptive purposes and not for the purpose of limitation, are intended to be broadly construed.

Moreover, the invention is not limited to the exact structures shown herein, because the sizes of the various parts may be varied to provide other structural embodiments without departing from the scope of the present invention.

The words sheet metal used herein and in the claims are intended to include sheet, strip or plate metal or tube stock having a wall of sheet metal thickness, any of which have the desired and necessary gauge, and may include steel or other metals from which it may be desired to construct the various parts.

The words standard pipe threads are intended to refer to the various standard pipe threads, which are standard in various countries of the world, all of which threads have V sides.

Having now described the features of the invention, the construction, manufacture and use of preferred forms of the same, and the advantages and results obtained by the improved constructions; the new and useful inventions, constructions and devices and reasonable mechanical equivalents thereof obvious to those skilled in the art, are set forth in the appended claims.

I claim:

1. In metallic container construction, a sheet metal wall provided with a neck, a sheet metal reinforcing ring surrounding said neck, interfltting complementary internal and external V- sided threads in the ring and neck, the metal the inner end of the neck, with the ancillary result that the axial stresses are localized in the threads and no axial stress is imposed upon that area indicated at M at which the neck joins the of the threaded parts of the ring and neck being formed to zig-zag shape and being displaced inward of the tubular loci of the unthreaded parts thereof, and the interfitting threaded and unthreaded parts of the ring and neck cooperatively holding the ring and neck assembled.

2. In metallic container construction, a sheet metal wall provided with a neck, a sheet metal reinforcing ring surrounding said neck, interfitting complementary internal and external V-sided threads in the ring and neck, the metal of the threaded parts of the ring and neck being formed to zig-zag shape and being displaced inward of 'metal wall provided with a neck, a sheet metal reinforcing ring surrounding said neck, interfltting complementary internal and external V- sided threads in the ring and neck, the metal of the threaded parts of the ring and neck being formed to zig-zag shape and being displaced inward of the tubular loci of the unthreaded parts thereof, the interfltting threaded and unthreaded parts of the ring and neck cooperatively holding the ring and neck assembled, and an outtumed flange at the outer end of the ring forming outtumed flange means for the outer end of the neck.

4. In metallic container construction, a sheet metal wall provided with a neck, a sheet metal reinforcing ring surrounding said neck, interfltting complementary internal and external V- sided threads in the ring and neck, the metal of the threaded parts of the ring and neck being formed to zig-zag shape and being displaced inward of the tubular loci of the unthreaded parts thereof, the interfltting threaded and unthreaded parts of the ring and neck cooperatively holding the ring and neck assembled, and engaged outtumed flanges-at the outer end'each of the ring and neck.

5. In metallic container construction, a sheet metal wall provided with a neck, a sheet metal reinforcing ring surrounding said neck, interfitting complementary internal and external V- sided threads in the ring and neck, the metal of the threaded parts of the ring and neck being formed to zig-zag shape and being displaced inward of the tubular loci of the unthreaded parts thereof, the interfltting threaded and unthreaded parts of the ring and neck cooperatively holding th ring and neck assembled, and outtumed shouldered flange means at the outer end of the ring and neck.

6. In metallic container construction, a sheet metal wall provided with a neck, a sheet metal reinforcing ring surrounding said neck, interfltting complementary internal and external V- sided threads in the ring and neck, the metal of the threaded parts of the ring and neck being formed tozig-zag shape and being displaced inward of the tubular loci of the unthreaded parts thereof, the interfltting threaded and unthreaded parts of the ring and neck cooperatively holding the ring and neck assembled, an outtumed flange at the outer end'of the ring, and the neck terminating in a tubular portion extending above the ring flange and forming therewith a shoulder.

7. The method of making a reinforced threaded sheet metal bung opening neck in a sheet metal neck inwardly of the tubular loci of the unthreaded parts of the same during the thread forming operation.

9. The method of making a reinforced threaded sheet metal bung opening neck in a sheet metal wall, the steps of forming an annular neck in a sheet metal wall to define an opening therein, telescoping a ring over said neck, simultaneously forming interfltting threads in the ring and neck, and forming an 'outturned flange at the outer end of the ring as astep of the method.

10. The method of making a reinforced threaded sheet metal bung opening neck in a I sheet metal wall, the steps of forming an annular neck in a sheet metal wall to define an opening therein, telescoping a ring over said neck, simultaneously forming interfltting threads -in the ring and neck, and, forming an outtumed flange at the outer end each of the ring and neck as a step of the method. 11. The method of making a reinforced threaded sheet metal bung opening neck in a sheet metal wall, the steps of forming an annular neck in a sheet metal wall to deflne an opening therein, telescoping a ring over said neck, securing the ring tothe neck against relative movement, and simultaneously forming interfltting threads in the ring and neck. JOSEPH FREASE. 

